1. Field of the Invention
This invention relates generally to a folding mechanism for a vehicle side mirror and, more particularly, to a folding mechanism for a vehicle side mirror, where the folding mechanism includes a plurality of détentes having different inner and outer ramp angles to prevent wear.
2. Discussion of the Related Art
Vehicles employ side mirrors that allow the vehicle operator to see behind and to the side of the vehicle. State of the art side mirrors are sometimes elaborate assemblies that include various options and features that increase the operator's ability to see objects, more safely operate the vehicle, provide a more aesthetically pleasing appearance, etc. One common vehicle side mirror design employs a folding mechanism that allows the mirror to be rotated relative to a mounting bracket so that the mirror can be folded towards the vehicle in both a forward and backward direction. The folding mechanism allows the mirror to be put in a more desirable configuration during parking or the like so that the side mirror has less chance of being damaged.
One particular side mirror folding mechanism design employs a pivot tube and pivot spring in combination with a case frame and base frame, where the case frame pivots relative to the base frame on the pivot tube. The base frame includes one or more détentes having angled edge ramps that cooperate with specially configured recesses in the case frame. When the case frame is in the unfolded, forward-folded or rearward-folded position, the détentes align with and are secured within the recesses. By applying manual or motorized pressure to the case frame, the case frame rotates on the pivot tube against the bias of the pivot spring. The ramped edges of the détentes allow the détentes to move out of the recesses.
It has been observed that this mirror folding design causes the détentes to wear at the outside edge of the ramps where the load from the pivot spring is concentrated. Such a localized stress point on the détentes causes a premature failure because the détentes wear out too quickly, reducing the ability of the folding mechanism to maintain the side mirror in the unfolded configuration.